| 摘要 |
PROBLEM TO BE SOLVED: To prevent a drive circuit from being turned on until a supply voltage rises to not less than a prescribed value in the drive circuit, and to prevent a through current from flowing to the transistor of an output stage in the drive circuit. SOLUTION: MOS transistors Q1, Q2 are cascaded. Output of an IC12 is applied to the gate of the MOS transistor Q1 and the gate of the MOS transistor Q2 via a Zener diode ZD2. When the output voltage of the IC12 is less than a Zener voltage, the MOS transistor Q2 is turned off and a supply voltage is applied to the gate of the MOS transistor Q4 via a resistor R6, thus turning on the MOS transistor Q4 in the output stage of the drive circuit 11. COPYRIGHT: (C)2009,JPO&INPIT
|
